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Having acquired the rights to the Kawaton my plan is to freshen it up and make it a runner. I have not worked on a triple since around 75 when i had the H1, but never went into the motor. I hear talk of seals being dated and the cases split to repair them. Will it hurt if the motor is started with bad seals. Will it smoke (how would you know). How does one tell if they need replacing? I'm a total noob to this motor and my question will bare that out. I believe this motor is still set up with the oil injection system and is hidden under the side bulbous pods under the tank. Hoof, you familiar enough with the 59 Manx to know if those tank additions are stock or something custom?
 

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Great to hear that you ended up with the bike.
 

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I hear talk of seals being dated and the cases split to repair them.
yup. But you would need the crank rebuilt as well (the seals are on the crank and it needs to be pressed apart and pressed back together). Best way to tell is to do a leakdown test. However if the engine was sealed up this entire time I would chance it that they may still be good. It's a long shot but I have bought triples that have been sitting for years and the crank seals were still good. Crank rebuilds run from $350-600.

Will it hurt if the motor is started with bad seals
Not initially but I wouldn't run it for long. The seals keep the trans oil out of the crankcase. If you have a seal leak the engine will begin to sump trans oil, until it runs out or hydrolocks.

Will it smoke (how would you know).
It will smoke like you are burning your trash while spraying for mosquitoes. seriously your neighbors will think your house is on fire. It will be white/blue oil smoke too since it is burning gear oil.

How does one tell if they need replacing?
Leakdown test (no more than 5 psi) or just start it and wait for the fire department to show up. You'll know.

I'm a total noob to this motor and my question will bare that out. I believe this motor is still set up with the oil injection system and is hidden under the side bulbous pods under the tank. Hoof, you familiar enough with the 59 Manx to know if those tank additions are stock or something custom?
The right side triangle shaped engine cover is the oil pump cover. It's not even gasketed. The tach drive goes in there as well. You'll see the oil pump and there will be three lines that go to the crankcase and one line that feeds from the oil tank. You can't run H2s on straight pre-mix without mods to the crank and cases. There are vanes that prevent gas and fuel from getting in there if you do and you'll seize the bottom end (ask me how I know, RIP 1975 H1).

oil-pump-h2a_mediumkar043357425_4c0b.jpg


Those lines take special seals so don't disturb them if you have to.
 

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A leak from a seal that pulls in trans fluid is one thing. A seal leak that pulls in air is a whole different problem. If it were mine I'd do a pressure test on the motor before trying to start it.

Craig
 

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oh man, i would love to get my hands on a decent priced H2... if you decide on selling it, let me know.
on the other hand, i urge you not to sell it, build it properly and enjoy it... it is truly an iconic bike.
 

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If your 2 stroke has bad bottom end seals, you are going to have a devil of a time starting it, and it won't make a nice pop-pop-pop 2 stroke sound, it will sound like it's "4-stroking" or running away with itself.
Also won't drop down to idle nicely, and your carbs will never function properly because they are completely dependant on lots of bottom end vacuum. Efficient scavenging will not happen either.

If your bottom end seals are bad your bike will basically run like a turd, if at all.
 

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To be fair h series inner seals do sit in fluid so often they aren't bad and when they are bad it isn't like a fully blown seal but more like a weep. I just remembered though I think there are scavenger pumps at the front of the block, you can pull those and see if trans oil leaks out. As for the end seals that block air, leak down test.
 

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Having acquired the rights to the Kawaton my plan is to freshen it up and make it a runner. I have not worked on a triple since around 75 when i had the H1, but never went into the motor. I hear talk of seals being dated and the cases split to repair them. Will it hurt if the motor is started with bad seals. Will it smoke (how would you know). How does one tell if they need replacing? I'm a total noob to this motor and my question will bare that out. I believe this motor is still set up with the oil injection system and is hidden under the side bulbous pods under the tank. Hoof, you familiar enough with the 59 Manx to know if those tank additions are stock or something custom?
That's a real humdinger of a disc on the front…. makes me wonder if there is something on there to compensate for the original head steady.
 
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